MonoGRAF Entities. Arcs

Arc

You can draw an arc by one of eight different methods using the following functions of the "arc" submenu:

• 3 points on arc - draws a 3-point arc. The first and second points are the arc's endpoints and the third is any point on the arc;


• begin, center, incl.angle - draws an arc by specified start point, center point and included angle;


• begin, center, chord - draws an arc by specified start point, center point and length of chord;


• begin, end, center - draws an arc by specified start, end and center points;


• begin, end, radius - draws an arc by specified start and end points and length of radius;


• begin, end, incl.angle - draws an arc by specified start and end points and included angle;


• begin, end, tangent - draws an arc by specified start and end points and starting direction;


• continue line - draws an arc as a smooth continuation of an existing line or arc (polyline arc).

Three point arcs

The "3 points on arc" function draws a 3-point arc. The first and second points are the arc's endpoints and the third is any point on the arc.

PROMPTS:

• Arc start point
• Arc end point
• Any point on the arc

If points are specified on a line you get the following error message:
   "The three points are co-linear"

PARAMETERS available via the "params" function of the control menu:
   "linetype, color, level of detail"

Begin, center, included angle

The "beg,cen,inc angl" function draws an arc by specified start point, center point and included angle.

PROMPTS:

• Arc start point
• Arc center
• Included angle

You may enter the angle as a value in the [-180,+180] degree interval or by 3 points, specifying the desired angle. If the two points coincide, you get the following error message:
   "The arc is not defined"

PARAMETERS available via the "params" function of the control menu:
   "linetype, color, level of detail"

Begin, end, center

The "beg,end,center" function draws an arc by specified start, end and center points.

PROMPTS:

• Arc start point
• Arc center
• Point on the second shoulder

The last prompt asks you to enter any point on the line specified by the arc center and the end point of the arc. The arc is drawn in counterclockwise direction. If two of the points coincide, you get the following error message:
   "The arc is not defined"

PARAMETERS available via the "params" function of the control menu:
   "linetype, color, level of detail"

Begin, end, included angle

The "beg,end,inc angl" function draws an arc by specified start and end points and included angle.

PROMPTS:

• Arc start point
• Arc end point
• Included angle

The included angle can be specified either as a value in the [-180,+180] degree interval, or by 3 points. If the two points coincide, you get the following error message:
   "The arc is not defined"

PARAMETERS available via the "params" function of the control menu:
   "linetype, color, level of detail"

Begin, center, length of chord

The "beg,cen,chord" function draws an arc by specified start point, center point and length of chord.

PROMPTS:

• Arc center
• Arc start point
• chord length

If you specify a positive value for the chord length, the arc is drawn counterclockwise. A negative value would invoke a clockwise drawn arc. This arc drawing method is ambiguous: 4 different arcs can be drawn from the same specifications. In MonoGRAF the smaller arc spanning a positive angle is drawn. If the two points coincide, you get the following error message:
   "The arc is not defined"

PARAMETERS available via the "params" function of the control menu:
   "linetype, color, level of detail"

Begin, end, tangent

The "beg,end,tangent" function draws an arc by specified start and end points and starting direction.

PROMPTS:

• Arc start point
• Select point for tangent
• Arc end point

The first two points determine the tangent line direction. If two points coincide, you get the following error message:
   "The arc is not defined"

PARAMETERS available via the "params" function of the control menu:
   "linetype, color, level of detail"

Line/arc continuation

The "continue line" function draws an arc as a smooth continuation of an existing line or arc (polyline arc).

PROMPTS:

• Select object
• Arc end point

The arc is drawn as a smooth continuation of one of the endpoints of the selected object (line or arc). The continued end is the one closer to the point with which the line or arc are selected. If the arc start and end points coincide, you get the following error message:
   "Arc not defined"

PARAMETERS available via the "params" function of the control menu:
   "linetype, color, level of detail"

Learning more for MonoGRAF basics